Spatially Enabling Service-Oriented Architectures with ArcGIS Server

SAP's ERP system is extended with GIS-based services to more accurately and efficiently assign assets in response to a chemical spill.

Organizations are becoming increasingly spatially literate and finding a greater need for open access to geospatial information and services. GIS technology has long been valued for enhancing communication and collaboration in decision making, effectively managing resources and assets, enhancing the efficiency of workflows, improving the accessibility of information, and generally offering tangible cost savings to organizations both large and small. In an effort to deliver geospatial information and functionality throughout an enterprise, organizations are choosing to extend their desktop GIS implementations with server-based GIS solutions that provide content and capabilities via Web services.

Technically, Web services are modular applications that correspond to recognizable business functions and offer a set of protocols by which they can be published, discovered, and used in a standards-based way. Organizationally, Web services are simply information technology (IT) assets that are often used as the basis for integration strategies that fuse content and capabilities in support of various business processes and initiatives. Web services provide the building blocks upon which broader IT strategies are based, such as the implementation of a service-oriented architecture (SOA).

Spatially enabling an SOA requires knowledge of not only the organizational business processes but also the robust capabilities and benefits that GIS offers. First, business processes should be distilled into common functions that can be delivered throughout the enterprise in conformance with the overall mission and goals of that organization, with services being created for each function. Second, business processes should be evaluated with an understanding of how GIS technology can extend and enrich those processes by providing value in overall efficiency, accuracy, accessibility, and cost savings. While these concepts are by no means revolutionary, they are evolutionary because they continue to bring technology, policies, and practices in harmony with organizational business processes.

Esri's Solutions for Geospatial SOA

Esri offers solutions today for developing a geospatial SOA that includes both desktop (ArcGIS Desktop) and server-based (ArcGIS Server) technology. These solutions enable organizations to author, publish, and serve their geographic knowledge to the broader organization. The role of ArcGIS Desktop is in defining and authoring the content that becomes the basis for common, reusable spatial services. GIS professionals can leverage their existing geographic expertise to author and design geospatial content, such as maps, globes, geoprocessing models, locators, and data management functions.

ArcGIS Server is a comprehensive Web-based GIS that provides out-of-the-box end user applications and services for mapping, analysis, data collection/editing, distribution, and management of spatial information. It provides a cost-effective, standards-based platform upon which ArcGIS Desktop users can easily publish and serve their geographic knowledge to the broader organization.

This diagram shows a sample configuration for delivering geospatial information and functionality throughout a local government using ArcGIS Server.

ArcGIS Server is a highly flexible and scalable technology that runs on world-class IT infrastructure and supports geospatial SOA initiatives. ArcGIS Server provides the technology foundation for organizations large and small to build and implement a set of GIS-based Web services. Some common services that support a geospatial SOA include map (2D) and globe (3D) services (transportation, demographics, physical environment, and asset maps/globes), locator services (geocoders and gazetteers), geoprocessing services (site selection models, dispersion/plume models, network analytics, raster analytics, image processing, etc.), and data management services (replication; data check-in/checkout; spatial extraction, transformation, and loading; and catalog services). Shared GIS services such as these can be used to add value to established business systems (e.g., work order, asset, and customer relationship management systems) and support enterprise-wide initiatives for collaborative computing.

Who Benefits from GIS-Based Services?

Users across an organization can benefit from shared GIS-based services. These users include GIS professionals, application developers, nontraditional GIS users, and IT administrators:

GIS ProfessionalsGIS professionals not only use ArcGIS Server as a platform to publish and promote their work in the form of shared maps, globes, processes, and functions, but they can also consume services that are published by others within their GIS community. GIS professionals with knowledge and expertise in specific domains can share their skills or tradecraft with other GIS professionals. For example, a GIS transportation engineer who is an expert in multimodal transportation models can publish and share network solvers that can be consumed by other GIS professionals and users within the organization. Sharing geographic knowledge helps GIS professionals standardize on geographic processing techniques and workflow scenarios, reduce software deployment costs, and ease implementation burdens.

Application DevelopersApplication developers can simply consume the services published by GIS professionals when building new or customizing existing applications without having to become a GIS expert. ArcGIS Server provides a rich Application Developer Framework (ADF) for both the J2EE and .NET 2.0 environments. It has multitiered components including fine-grained objects, coarse-grained objects, Web controls, Web services, and task assemblies. The ArcGIS Server ADF also provides a tight IDE (Visual Studio, Eclipse, and Sun Java), an extensive help system with platform-specific code examples, and rich Web user interface components that natively employ AJAX techniques and offer game-style navigation capabilities. The ArcGIS Server ADF offers a common, extensible, and task-oriented framework that supports ArcGIS Desktop, ArcGIS Explorer, ArcGIS Engine, and browser-based clients for traditional desktop, thin-client, mobile, and enterprise deployments.

Nontraditional GIS UsersNontraditional GIS users can consume GIS-based Web services via focused applications where geospatial services are infused into the fabric of their application. Depending upon the level of integration, users may not even realize they are implementing GIS techniques and processes. Making GIS transparent to users via services enriches their applications while ensuring they adhere to the best practices and techniques as defined by GIS professionals.

IT AdministratorsIT administrators can consume and integrate GIS services into the broader IT landscape in support of various business workflows. For example, GIS services can be integrated with work order management systems, financial systems, supply chain management, business intelligence reporting, and executive dashboards to name just a few.

Examples for Local Governments

Using ArcGIS Server, GIS users in a public works department could publish a set of services and applications to satisfy the needs and requirements not only for their department (e.g., map the location of current construction projects) but also for other city departments (such as police or fire), other regional entities (emergency 911, sheriffs departments), or state agencies (such as departments of transportation or state police). The sharing of services and applications can include national participation with federal agencies (Department of Homeland Security, Federal Emergency Management Agency, etc.). Even public/private relationships can be fostered with private utilities, local businesses, or real estate firms.

A geospatial service-oriented architecture allows common GIS functions to be delivered as services throughout the enterprise.

In another example, a Call Before You Dig application might leverage shared services, such as geocoding (identify a dig location), mapping (generate a map of the dig site), proximity (find all electric, gas, phone, cable assets within a certain distance of a dig site), reporting (regulatory compliance), and routing (dispatching of field crews/inspectors).

Integrating ArcGIS Server with other key business systems can extend the value of those systems by increasing accuracy, efficiency, and productivity. For example, an enterprise resource planning (ERP) tool can be used to identify government personnel with specialized skills to assist in a chemical spill accident. GIS services can be leveraged by the ERP tool to more accurately understand the location of those personnel in relation to the event and use calculated travel times to allocate appropriate resources, while avoiding potentially dangerous areas downwind from the accident location. In this case, GIS services extend the value of the ERP system and provide a more timely and efficient response.

Summary

Organizations today are being challenged to be more efficient, accurate, and accessible. To deal with these challenges, IT departments are moving increasingly toward SOAs to provide a framework for technology, policies, and practices by which they can be organized in an effort to deliver the right services to the right people at the right time and in the right place. GIS is a proven and valued technology that plays an important role in today's SOA strategies and initiatives. With desktop and server-based GIS solutions, such as ArcGIS Desktop and ArcGIS Server, organizations can integrate GIS into their existing workflows and solve today's challenges of providing open access to common geospatial data, services, and applications from within their organizations and beyond.